Method of trimming wicks



June 13, 1939. R HOFFMAN 2,162,401

METHOD OF TRIMMING WICKS Filed Aug. 25, 1936 INVENTOR.

Ezmaifa/z Hoffman. BY

@a M s fi ATTORNEY6 Patented June 13, 1939 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates as indicated to wicks. but has reference more particularly to wicks for oil burning stoves and to methods of treating and trimming the same.

In preparing cylindrical Wicks for oil burning stoves, it has heretofore been the practice to cut the wick which is received in the form of a long tube into short lengths of the desired size and insert one end of each length of wick in a cylindrical holder of perforated metal, clamping the wick in such holder by means of prongs formed integrally with the holder and bent outwardly into engagement with the inner wall of the wick at the base of the wick. The exposed end of the wick is usually rough and has loose threads projecting therefrom as the result of the cutting or trimming operation. If the end of the wick is lighted while in this condition, an uneven flame will be produced. To produce a more uniform flame, it is the practice to invert the wick so as to place the exposed end on a hot plate, which burns off the loose threads and chars the entire end. This makes the wick appear as though it has been in use for a long period, and is also objectionable because the charred fragments get on the remaining surface of the wick and make it appear dirty, especially after handling.

It is a primary object of the invention to overcome the defects and disadvantages of the foregoing practice and to provide a wick of the character described which will retain its cylindrical form under various conditions of handling and use, which is neat and attractive in appearance when purchased, and which, when lighted, will 5 produce a substantially even flame.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

40 The annexed drawing and the following de scription set forth in detail certain means and one mode of carrying out the invention, such disclosed means and mode illustrating, however, but one of various ways in which the principle of the 4,5 invention may be used.

In said annexed drawing:

Fig. 1 is a view of a fragment of the woven tubing from which the wicks are out; Fig. 2 is a view, partly in side elevation and partly in sec- 50 tion, of the wick mounted in its holder; Fig. 3 is a view showing the manner in which the wick is dipped to impregnate the exposed end portion thereof; Fig. 4 is a fragmentary cross-sectional view of the exposed end of the wick after dip- 5 ping; Fig. 5 is a view showing one method of trimming the wick; Fig. 6 is a view similar to Fig. 4, but showing the trimmed wick; Fig. '7 is a view showing another method of trimming the wick; and Fig. 8 is a view similar to Fig. 6, but showing the wick as trimmed by the method indicated in c Fig. '7.

Referring more particularly to the drawing, there is disclosed in Fig. 1 a length of woven fabric tubing l, of the desired diameter, which, after being received in this form, is cut as indicated 10 by the dot and dash lines into portions 2, of a length slightly greater than the length of the wicks to be formed from such portions.

Each of the wicks 2 as thus formed is inserted into a cylindrical holder 3 of perforated metal, 15 the base of the wick being clamped in such holder by means of prongs 4 formed integrally with the holder and bent outwardly into engagement with the inner wall of the wick. The exposed end 5 of the wick, as will be noted, is rough and 20 has a multiplicity of loose threads projecting therefrom, so that the wick, if lighted while in this condition, will produce an uneven flame.

Instead of charring this end of the wick, as has heretofore been the practice, I invert the wick as 25 shown in Fig. 3, and dip the exposed end 5 thereof into a molten substance 6, which preferably consists of a material of a combustible nature, such as a mixture of various waxes and their derivatives. The molten substance may be thinned, 30 if desired, as by the addition of small amounts of cocoabutter. This dipping results in an impregnation of the exposed end of the wick by the molten substance to a point indicated by reference numeral 1. After the end of the wick has been thus impregnated, the wick is mounted on a spindle (not shown) and rapidly rotated to remove the excess molten material, the remaining material when cooled becoming hard so as to make the impregnated end of the wick more or less stiff and unyielding, thereby preserving the cylindrical shape of the wick and facilitating the trimming operation to be now described.

The wick is mounted on. a mandrel 8, having a portion 9 underlying the impregnated end of the wick and formed of rubber or like resilient substance. The mandrel and wick are rotated and during such rotation, a rapidly rotating circular cutter I0 is moved towards and through the impregnated portion of the wick so as to cut off a substantial portion thereof, as indicated by the dot and dash line in Fig. 6, but leaving a substantial portion of the impregnated end on the wick. Since the impregnated end of the wick is, as previously stated, more or less stiff and unyielding, 6i

the wick is cut or trimmed squarely and no loose threads are left or formed. Consequently, an even flame is produced as soon as the wick is placed in use. Furthermore, no diflicultyis encountered in lighting the wick, and in fact, such lighting is facilitated, as the material with which the trimmed end of the wick is impregnated is of a readily combustible nature. Charring is avoided and the original neat and attractive appearance of the wick is preserved.

In some cases, it is desired to trim the wick so as to produce a beveled end thereon, as indicated in Fig. 8. This is accomplished by mounting the wick in a hollow chuck H, as shown in Fig. 7, the wick being prevented from collapsing by means of an expansible mandrel l2 within the chuck and which bears against the inner wall of the wick. The impregnated end of the wick which is to be trimmed projects beyond the end of the chuck and the chuck and wick are rotated. During such rotation, a cup-shaped cutter I3 is rapidly rotated about an axis non-parallel with that of the-wick and cutting edge I of this cutter produces the desired beveled end of the wick,

as shownin Fig. 8.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the means herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

I therefore particularly point out and distinctly claim as my invention:

1. The method of trimming wicks which comprises impregnating only one end of the wick with a hardenable substance of a combustible nature containing wax, mounting said wick on a mandrel, rotating said mandrel to thereby rotate said wick, and cutting off a portion of said impregnated end during such rotation so as to leave a smooth end on the wick.

2. The method which comprises mounting a tubular wick in a tubular holder in such a manner as to leave an end portion of the wick exposed, impregnating a portion of said exposed end portion of the wick with a hardenable substance of a combustible nature containing wax, mountingsaid' holder on a mandrel, rotating said mandrel to thereby rotate the holder and wick, and during such rotation cutting off a portion of said impregnated end of the wick so as to leave an end on the wick which is free from projecting threads and the like.

RUDOLPH HOFFMAN. v 

